In the art of filling narrow necked bottles with liquid, particularly carbonated liquids, the liquid must be discharged into the neck of the bottle so that the air present in the bottle may escape without disturbing the entering stream of liquid. More importantly, the liquid must be discharged into the bottle with as little turbulence as possible so as to minimize disturbing the liquid.
It is common knowledge to pour the contents of a carbonated liquid from a bottle down the sides of a tall glass to minimize the loss of carbonation. Some effort has been made to fill bottles by causing the liquid to flow down the inside walls of the bottle rather than to simply enter the bottle and strike the bottom wall or discharge into the contents of the partially filled bottle. Publication DT-GM 72 38 305 describes a filling device having a chamber of circular cross section. Fluid enters the device through a channel which discharges the fluid tangentially onto the circular wall of the chamber. As the fluid on entering the chamber changes direction, it flows in a spiral path and thereby acquires a certain amount of angular momentum. Because the spiral path is very short, the angular momentum is not very great and the swirling component quickly disappears along the circular chamber. Only a small portion of the fluid continues the swirling motion down the sidewall of the container. In addition, different components of the fluid flow are discharged from the opening at different angular velocities so that turbulence results at the mouth of the bottle and continues throughout the travel down into the bottle.
Another design used to impart a torsional flow is the use of metal guides similar to turbine blades. Such guides with their numerous edges disturb the smooth flow and cause a plurality of eddy currents to develop. Further the metal guides are difficult to clean. Because the chamber in this device is also circular, as stated previously, only a limited angular velocity is imparted by the guides and the angular component is quickly lost after the liquid enters the container. The plurality of blades divide the flow into a plurality of streams having different angular velocities which result in turbulence as the flows intermix at different velocities and angles of discharge.